AUDIE CORNISH, HOST:

Secretary of Defense Leon Panetta said today that U.S. troops in Afghanistan hope to shift a way from a combat mission by the end of next year. That's somewhat sooner than anyone in the Obama administration has said before. Panetta is traveling this week to consult with NATO defense ministers. His statement today does not change one important fact: large numbers of American troops will stay at least till the end of 2014.

Joining us now to explain what's new here and what's not is NPR's Pentagon correspondent Tom Bowman. And, Tom, to begin, give us a little bit more detail about what Secretary Panetta had to say.

TOM BOWMAN, BYLINE: Well, Audie, the secretary said, quote, "Hopefully, by the mid to latter part of 2013, we'll be able to make a transition from a combat role to a training advise and assist role." And what that means essentially that U.S. and NATO troops would have the Afghans take that combat role, and then they would provide training, but also help with everything from logistics and medevacs to bomb disposal.

And one of Panetta's aides sent me an email tonight, saying: We're consulting with our allies this week about the idea of a transition to a support role in Afghanistan in 2013. But he quickly added: We'll be working with the Afghans, including fighting insurgents until the end of 2014.

CORNISH: Till the end of 2014, that part of a policy doesn't change, is that right? I mean, that's long been the target date.

BOWMAN: That's right. And it appears what's going on here is they want to shift a little faster to that advise and assist role for Afghan forces to make sure they're ready for that 2014 handover. And I've been out in the field with Afghan forces, and clearly, they're not ready. Their very best junior partners and senior U.S. officers will say that the Afghan security forces, their performance is spotty.

So by beginning the training mission sooner - and, of course, that clock is ticking, and there's a war-weariness in both the NATO countries and the U.S. - the Obama administration wants to make sure that these Afghans are ready by that handover date in 2014.

CORNISH: Is this anything like Iraq in terms of U.S. troops moving out of harm's way, not taking on as much of a combat role over time?

BOWMAN: You know, not really. At this point in Afghanistan, there are a lot of small combat outposts supporting the Afghans. And you can still take rocket fire, mortar fire from these outposts. And, of course, if you're an adviser out on patrol with them, the particular threat is roadside bomb. So it's not exactly like what happened in Iraq. And toward the end, a lot of the U.S. troops who were inside large bases and pretty much hunkered down.

CORNISH: So, is this a big change or not?

BOWMAN: Well, you know, at this point, it's kind of hard to say. You know, Secretary Panetta was saying hopefully to be able to make this transition in late 2013. That keyword is hopefully. And the other thing to keep in mind is that, you know, part of this is, you know, make - if you want to make that transition in 2014, again, you have to start in 2013, if not earlier.

CORNISH: So bottom line, do U.S. troops leave Afghanistan any sooner?

BOWMAN: The quick answer is no. The official policy is that they stay until the end of 2014. That hasn't changed. In fact, Pentagon planners are still looking at how many would stay after 2014, and a number I've been hearing is it could be as high as 15,000 U.S. troops.

CORNISH: Tom, thank you.

BOWMAN: You're welcome, Audie.

CORNISH: NPR's Pentagon correspondent Tom Bowman. Transcript provided by NPR, Copyright NPR.